Virtual Top-Quark Effects on the H->bb-bar Decay at Next-to-Leading Order in QCD

Original · EN

By means of a heavy-top-quark effective Lagrangian, we calculate the three-loop corrections of O(alphaₛ² GF Mₜ²) to the H->bb-bar partial decay width of the standard-model Higgs boson with intermediate mass Mₕ<<2Mₜ. We take advantage of a soft-Higgs theorem to construct the relevant coefficient functions. We present our result both in the MS-bar and on-shell schemes of mass renormalization. The MS-bar formulation turns out to be favourable with regard to the convergence behaviour. We also test a recent idea concerning the naive non-abelianization of QCD.